Cooker

ABSTRACT

A cooker in which a receptacle with a pot for holding ingredients and a heater for induction heating the pot is supported by a main unit so that it can be inclined freely, consists of an angle control unit which provides driving force for inclining the receptacle to the receptacle, a controller for controlling the angle control unit, and shall be capable of automatically inclining the receptacle and uniformly sauteing the ingredients.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a cooker which uses induction heatingto heat a pot for cooking by sauteing or other means.

2. Description of the Prior Art

Progress in technology which uses induction heating to heat magneticpots has led to the recent development of rotary cookers which useinduction heating to heat rotary pots for automatic sauteing. Anelectromagnetic cooker disclosed in the Japanese Patent ApplicationLaid-Open No. 63-175375 is such an example, and FIG. 33 shows a partialcross-section of the side of the cooker.

In FIG. 33, receptacle 2 is mounted on top of main unit 1, which has abuilt-in heating power supply, by hinge 3 so that it can rotate freely,and supported and fixed by support member 4 at a desired inclinationangle. Support member 4 consists of first support lever 4b and secondsupport lever 4c which are joined together by pin 4a, and supports andfixes receptacle 2 at a desired angle by tightening pin 4a. Pot 7 islocated at the central part of receptacle 2 in such a way that it can berotated on axis 9 by driving unit 8 at the bottom. Induction heatingcoil 6 is wired around pot 7 via heat insulator 5. Lid 10 is screwedonto the top of receptacle 2 and slip ring 11 is provided between lid 10and pot 7 to prevent ingredients inside pot 7 from escaping fromreceptacle 2. In addition, there is small lid 12 on the central top ofthe lid for inserting seasonings. Numbers 13 and 14 are control unitsfor rotation speed and heating temperature or time, respectively, and 15is ingredients.

As an example to saute ingredients, using the cooker described above,incline receptacle 2 at a desired angle by support member 4 and turn oninduction heating coil 6 to heat the outside of pot 7 while actuatingdriving unit 8 to rotate pot 7. Then, put oil into pot 7 and stop therotation when oil spreads all over pot 7. Put ingredients 15 to besauteed into the pot, cover with lid 10 and rotate pot 7. Then,ingredients 15 are heated, stirred and sauteed within pot 7. At a propertime, open small lid 12 to add seasonings and cooking is over.

The conventional electromagnetic cooker is configured and used asdescribed above.

(a) However, since receptacle 2 of the above electromagnetic cooker isinclined manually, it is not easy to use. There is a risk of users'getting burnt especially when changing the inclination angle of thereceptacle during operation, .

(b) The pot for holding ingredients is heated by induction heating coil6. However, heating coil 6 consists of only one layer, thusproviding-only a single cooking pattern. Therefore, the cooker can doonly sauteing, and is thus limited in its application range.

(c) The types of cooking possible with this cooker is limited.

(d) In addition, its heating method is very simple, cooking methods andheating times are limited, resulting in a narrow application range.

(e) As the rotation speed of the pot is fixed and does not change duringcooking, it has been difficult to enhance the sauteing performance.

(f) Induction heating coil 6 is wired between the side and the bottom ofcooking pot 7 via heat insulator 5 to heat ingredients 15 inside the potfrom the outside. Therefore, when cooking pot 7 is inclined, the top ofcooking pot 7 where there are no ingredients is also heated, resultingin a waste of electricity as well as a large size, complex structure andhigh production cost for induction heating coil 6.

(g) Furthermore, since cooking pot 7 is rotated at a fixed speed andheated uniformly, ingredients 15 do not contact all parts of cooking pot7, thus take a long time to cook. In addition, induction heating coil 6is wired between the side and the bottom of cooking pot 7 via heatinsulator 5 to heat ingredients 15 from the outside. Therefore, whencooking pot 7 is inclined, the top of cooking pot where there are noingredients 15 is heated, resulting in a waste of electricity, and alarge size, complex structure and high production cost for inductionheating coil 6.

(h) Cooking pot 7 fixed on the tip of rotary axis 9 is rotated byactuating driving unit 8. Flange 7a of cooking pot 7 is rotated while incontact with slip ring 11 fixed on stationary lid 10 to seal up the pot.Therefore, too tight a sealing results in increased friction, thewearing of contact surfaces, and the generation of a gap which hindersthe rotation of cooking pot 7. On the other hand, too loose a sealingresults in soup running out from the gap to the inside of receptacle 2.Since cooking pot 7 is fixed, it is difficult to clean after cookingand, accordingly, it becomes easily dirty.

(i) When ingredients are to be sauteed, for instance, users must feelthe temperature of the pot from the ambient temperature by putting theirhands into cooking pot 7. Therefore, there is a risk of their gettingburnt when they put their hands into the pot. Since the temperature ofthe cooking pot is unknown during cooking, heating temperature iscontrolled by the perception and experience of users. As a result, theycannot go away from the rotary cooker during cooking. If they go awayfrom the cooker, the temperature of the cooking pot goes too high,resulting in scorching and an eventual danger of fire. In addition, whenthe cooking pot is heated continuously without ingredients inside, itbecomes too hot and damages the receptacle.

(j) Cooking using the electromagnetic cooker is carried out as describedabove. Since the cooking temperature is unknown, the timing for addingoil and seasonings and the timing for taking out sauteed food rely onthe perception and experience of cooks. In addition, if cooks go awayfrom the cooker during cooking, ingredients are scorched and there is adanger of fire.

SUMMARY OF THE INVENTION

(a) The first embodiment overcomes the above problems of theconventional cooker. It is therefore an object of the first embodimentto provide a cooker which enables users to freely change the inclinationangle of the pot for holding ingredients during cooking without fear ofgetting burnt.

(b) It is an object of the second embodiment to provide an easy-to-userotary cooker which enables various types of cooking.

(c) It is an object of the third embodiment to provide a rotary cookerwhich enables users to select the inclination angle of the receptaclefreely and set a cooking program according to type of cooking in orderto prepare their desired meals automatically.

(d) It is an object of the fourth embodiment to provide a rotary cookerwhich is configured in such a way that the inclination angle of thecooking pot and the heating temperature range can be changed, enablingusers to set cooking programs by selecting the inclination angle andheating temperature range according to the type of cooking in order toautomate cooking according to programs.

(e) It is an object of the fifth embodiment to provide a rotary cookerwhich is equiped with a device to change the rotation speed of the potfor enhanced sauteing performance.

(f) It is an object of the sixth embodiment to provide an economicalelectromagnetic cooker which is low priced and eliminates electricitywaste.

(g) It is an object of the seventh embodiment to provide an inexpensiveand economical cooker which can change the rotation of the cooking potregularly or at random, and which combines concentrated heating bystopping the rotation and stirring/heating by changing the rotationspeed of the cooking pot regularly or at random, thus making it idealfor cooking that requires strong heat.

(h) It is an object of the eighth embodiment to provide a cooker whichcan maintain airtightness between the cooking pot and the pot lid veryeasily, and which features high ease of operation.

(i) It is an object of the ninth embodiment to provide an easy-to-usecooker which can optimize the temperature of the cooking pot forcooking, sauteing for instance, and incorporates programs of cookingconditions for various types of cooking so that desired meals can beprepared automatically according to the type of cooking.

(j) It is an object of the tenth embodiment to provide a safe andeasy-to-use rotary cooker which displays cooking temperatures andenables anyone to prepare good meals without reliance on his/herperception and experience.

In order to attain the above mentioned objects, the present invention isconstructed as follows. (a) According to the first embodiment as shownin FIGS. 1 to 3, a cooker in which a receptacle with a pot for holdingingredients and a heater for induction heating the pot is supported by amain unit so that it can be inclined freely comprises an angle controlunit which provides driving force for inclining the receptacle to saidreceptacle and a controller for controlling the angle control unit. (b)According to the second embodiment as shown in FIG. 7, a cooker in whicha receptacle with a pot for holding ingredients and a heater forinduction heating the pot is supported by a main unit so that it can beinclined freely comprises an angle control unit which provides drivingforce for inclining the receptacle to the receptacle and a controllerfor controlling said angle control unit.

Induction heating coils which constitute said heater consist of a coilfor heating the bottom of the pot and a coil for heating the side ofsaid pot, each of which is equipped with input control means and inputswitching means to heat the side or bottom only or both of themsimultaneously.

(c) According to the third embodiment as shown in FIGS. 4 to 6, a cookerin which a receptacle with a pot for holding ingredients and a heaterfor induction heating the pot is supported by a main unit so that it canbe inclined freely comprises an angle control unit which providesdriving force for inclining the receptacle to said receptacle, acontroller for controlling the angle control unit, an angle detector,and a memory for storing an angle setting program.

Said controller can control the inclination angle of said cooking pot soas to make the angle detected by the angle detector coincide with theangle preset by the angle setting program.

(d) According to the fourth embodiment as described in FIGS. 8 to 10, acooker in which a receptacle with a pot for holding ingredients and aheater for induction heating the pot is supported by a main unit so thatit can be inclined freely comprises an angle control unit which providesdriving force for inclining the receptacle to the receptacle, acontroller for controlling the angle control unit, an angle detector, amemory for storing an angle setting program and activation time settingprogram, and a timer.

Said controller can control the inclination angle of the receptacle soas to make the angle detected by the angle detector coincide with theangle preset by said angle setting program, and control the activationtime for the heater so as to make the time preset by the activation timesetting program coincide with the time measured by the timer.

(e) According to the fifth embodiment as shown in FIG. 11, a cooker inwhich a receptacle with a pot for holding ingredients, a rotationstructure for rotating the pot and a heater for induction heating thepot is supported by a main unit so that it can be inclined freelycomprises an angle control unit which provides driving force forinclining the receptacle to said receptacle, a controller forcontrolling the angle control unit, and a device for changing therotation speed of said pot.

(f) According to the sixth embodiment as shown in FIGS. 13 to 15, acooker in which a receptacle with a pot for holding ingredients, arotation structure for rotating the pot and a heater for inductionheating the pot is supported by a main unit so that it can be inclinedfreely comprises an angle control unit which provides driving force forinclining said receptacle to the receptacle, a controller forcontrolling the angle control unit.

The induction heating coil of the induction heater is wired around thelowest part of the inclined pot.

(g) According to the seventh embodiment as shown in FIGS. 16 to 20, acooker in which a receptacle with a pot for holding ingredients, arotation structure for rotating the pot and a heater for inductionheating the pot is supported by a main unit so that it can be inclinedfreely comprises an angle control unit which provides driving force forinclining said receptacle to said receptacle, a controller forcontrolling the angle control unit, and a device for changing therotation speed of said pot.

Said device for changing the rotation speed of said pot can heat saidingredients concentratedly with the induction heater by stoppingintermittently or decelerating the rotation of the pot.

(h) According to the eighth embodiment as shown in FIG. 21, a cooker inwhich a receptacle with a pot for holding ingredients and a heater forinduction heating the pot is supported by a main unit so that it can beinclined freely comprises an angle control unit which provides drivingforce for inclining the receptacle to said receptacle, a controller forcontrolling the angle control unit, and a pot lid with a port on thepot.

(i) According to the ninth embodiment as shown in FIGS. 22 to 25, acooker in which a receptacle with a pot for holding ingredients and aheater for induction heating the pot is supported by a main unit so thatit can be inclined freely comprises an angle control unit which providesdriving force for inclining the receptacle to said receptacle, acontroller for controlling the angle control unit, a temperaturedetector in contact with the pot for detecting the temperature of thepot, and cooking condition control means for controlling cookingconditions according to cooking programs based on type of cooking forthe ingredients and temperatures detected by the temperature detector.(j) According to the tenth embodiment as shown in FIGS. 26 to 32, acooker in which a receptacle with a pot for holding ingredients and a,heater for induction heating the pot is supported by a main unit so thatit can be inclined freely comprises an angle control unit which providesdriving force for inclining the receptacle to said receptacle, acontroller for controlling the angle control unit, a contact with athermosensitive device, transport means for bringing this contact intocontact or out f contact with the outside of the pot and temperaturemeasurement means for measuring the detection temperature of thethermosensitive device.

The above and other objects, features, and advantages of the presentinvention will become more apparent from the following description whentaken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram showing a partial cross-section of the front of anembodiment of a cooker according to the present invention;

FIG. 2 is a diagram showing a partial cross-section of the side of theembodiment;

FIG. 3 is a diagram illustrating the control circuit;

FIG. 4 is a diagram showing a cross-section of the receptacle of anembodiment of a cooker according to the invention;

FIG. 5 (a) is a diagram showing the side, FIG. 5 (b) enlarged diagramshowing the angle detection unit, and FIG. 5 (c) diagram showing apartial cross-section of the front of an embodiment of a cookeraccording to the invention;

FIG. 6 is a block diagram describing the cooking control configuration;

FIG. 7 (a), (b) and (c) are cooking time charts;

FIG. 8 (a) is a diagram showing the side of the inclining unit of thereceptacle and FIGS. 8 (b) and (c) are enlarged diagrams showing the keyparts of an embodiment of a cooker according to the invention;

FIG. 9 is a block diagram describing the cooking control configuration;

FIGS. 10 (a), (b), (c) and (d) are cooking time charts for sauteed,curry and "tempura," respectively;

FIG. 11 (a) is a diagram showing the front of an embodiment of a cookeraccording to the invention and FIG. 11 (b) is a diagram illustratingchanges in rotation speed;

FIG. 12 is a diagram showing the configuration of an embodiment of acooker according to the invention;

FIG. 13 is a diagram showing a cross-section of X--X of FIG 12;

FIG. 14 is an illustration of an induction heating coil;

FIG. 15 is a diagram showing the key parts of another embodiment of acooker according to the invention;

FIG. 16 is a diagram of the configuration of an embodiment of a cookeraccording to the invention;

FIG. 17 is a detailed diagram of part of the embodiment shown in FIG.16;

FIG. 18 is a timing chart describing the operation of the presentinvention;

FIG. 19 is a diagram of the configuration of another embodiment of acooker according to the invention;

FIGS. 20 (A) and (B) are diagrams of the induction heating coils shownin FIG. 19;

FIG. 21 is a diagram of the configuration of the embodiment according tothe invention;

FIG. 22 is a diagram showing a cross-section of the side of theembodiment according to the invention;

FIG. 23 is a diagram showing a cross-section of key parts of theembodiment;

FIG. 24 is a diagram describing the configuration of a controller;

FIG. 25 is a sauteing timing chart.;

FIG. 26 is a diagram showing a cross-section of the embodiment of acooker according to the invention;

FIG. 27 is a diagram of a cross-section of driving means (60) shown inFIG. 26;

FIG. 28 is a block diagram of control means (23) shown in FIG. 26;

FIG. 29 (a) is a timing chart for the driving control of a contact ofthe embodiment, (b) timing chart showing the relationship betweencontact control and pot driving means control, (c) timing chart showingthe relationship between contact control and induction heating coilcontrol, and (d) timing chart showing the relationship between contactcontrol and the control of pot driving means and induction heatingcoils;

FIG. 30 is a flow chart of the cooking programs of the embodiment;

FIG. 31 is a diagram describing control information on the cookingcourses of the embodiment;

FIG. 32 is a timing chart describing the operation of an embodiment of arotary cooker in the case of a sauteing course; and

FIG. 33 is a diagram showing an example of a conventionalelectromagnetic cooker.

DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1 shows a partial cross-section of the side and FIG. 2 a partialcross-section of the front of a cooker according to the firstembodiment.

Numbers 1 to 7 in the figure refer to the same or equivalent parts asthose of conventional cookers. Number 20 is a support, 21 driving motor,22 first gear, 23 second gear, 24 their axis, 25 bracket, 26 brake, 27aand b limit switches, 28 control circuit and 29 operation switch.

As shown in the figure, ingredients are placed inside pot 7 of therotary cooker and cooked by rotating pot 7 with a rotating unit (notshown in the figure), heating it with induction heating coils 6 andinclining receptacle 2, when necessary.

In the above rotary cooker according to the invention, a receptacleinclining unit consists of an inclination angle control unit, aninclination angle retention unit and a controller. The inclination anglecontrol unit is furnished with driving motor 21 fixed on support 20,first gear 22 coupled with the axis of motor 21 and second gear 23engaged with the first gear. Bracket 25 fixed at the bottom ofreceptacle 2 is fitted with second gear 23 and can rotate freely on axis24 supported by support 20. Therefore, when driving motor 21 is started,bracket 25 fixed on second gear 23 rotates at the same time as firstgear 22 and second gear 23 engaged with the first gear rotate.receptacle 2 fixed on bracket 25 is accordingly inclined around axis 24.That is, receptacle 2 is inclined by the starting of motor 21. Inaddition, the angle retention unit can incline receptacle 2 at a desiredangle by starting brake 26 when the inclination angle reaches a desiredangle, and maintain the desired angle. To incline and maintainreceptacle 2 at a desired angle of inclination, controller 28 isactuated by the operation of switch 29. Therefore, the inclination angleof receptacle 2 can be changed during cooking.

As shown in FIG. 2, the inclination angle of receptacle 2 can beselected freely between horizontal position a of pot 7 and position dwhen receptacle 2 contacts the bottom of main unit 1. For this purpose,main unit 1 is furnished with limit switches 27a and 27b so that whenreceptacle 2 touches limit switch 27a or 27b at horizontal position aand maximum inclined position d, motor 21 stops operation. FIG. 3 showsthe control circuit of the controller for the above operation.

In this embodiment, the angle control unit uses gears, but ball screws,links and cams can be used instead of gears to control the angle ofinclination.

Since the cooker according to the present invention incorporates areceptacle inclining unit which consists of an angle control unit forinclining a receptacle at a desired angle, an angle retention unit forkeeping the receptacle inclined at the desired angle and a controller,it allows the receptacle to be freely inclined through switch operationduring cooker operation, thus greatly improving the operational ease ofthe cooker.

FIG. 4 is a diagram showing a cross-section of the receptacle of acooker according to the second embodiment. In the figure, number 7 is apot, 20 first coil, 21 second coil, 22 first coil input controller, 23second coil input controller, and 24 input switch. The cookerincorporates an angle control unit and a controller described in FIG.33.

In the figure, a pot rotation driving unit and a receptacle incliningunit are omitted.

As shown in the figure, heating coils consist of the first coil forheating the bottom of the pot and the second coil for heating the sideof the pot. Input switch 24 is used to turn on the first or second coilonly or both of them.

As a result, only the first coil is used for roasting meat, while onlythe second coil is used for preparing curry and stew. For sauteingvegetables and noodles, it is recommended to use both of these coils.

In this way, the cooker can change heating methods according to type ofcooking, resulting in an increased types of meals to be prepared by thisrotary cooker, expanded application range and improved operational easeof the cooker.

According to the present invention, the rotary cooker incorporatesheating means which consist of the first coil for heating the pot bottomand the second coil for heating the pot side to heat the pot by usingeither one of them or both of them, thus greatly increasing the types ofmeals to be prepared by this rotary cooker and improving its operationalease.

FIG. 5 (a) is a diagram illustrating the side of the receptacleinclining unit, (b) an enlarged diagram of the angle detection unit, and(c) a diagram showing a partial cross-section of the front of a cookeraccording to the third embodiment. FIG. 6 is a diagram of cookingcontrol configuration. FIG. 7 (a), (b) and (c) are cooking time charts.In these figures, number 2 is a receptacle, 6 heating coil, 7 pot, 18rotation driving unit, 18a motor, 18b driving wheel, 115 housing, 120inclining unit (angle control unit), 21 driving motor, 22 first gear, 23second gear, 25 bracket, 24 axis, 26 brake, 127 angle detection unit,128 infrared transmission unit, 129a to d flange plates, 130 controller,1 base, 20 support, 33 limit switch, 40 input interface, 41 outputinterface, 42 clock control unit, 43 timer, 44 CPU, 45 memory, 46 powersupply, and 47a and b cooking course input switches.

As shown in FIG. 5, a rotary cooker according to the present inventionincorporates pot 7, rotation driving unit 18 for rotating pot 7,receptacle 2 with heating coil 6 for induction heating cooking pot 7, aninclination angle setting device which is comprised of inclining unit 20for inclining receptacle 2, brake 26 for maintaining the inclinationangle, and inclination angle detection unit 127, and controller 130.

Furthermore, rotation driving unit 18 described above consists ofdriving motor 18a and driving wheels 18b, and heating coils areinstalled inside housing 115. Inclining unit 120 is comprised of drivingmotor 21 fixed to support 20, first gear 22 coupled with the axis ofmotor 21 and second gear 23 engaged with first gear 22. Bracket 25 fixedto the bottom of housing 115 is mated with axis 24 so that it can rotatefreely. Axis 24 fitted with second gear 23 is fixed to support 20.Therefore, the actuation of motor 21 rotates gears 22 and 23 and bracket25 simultaneously to incline receptacle 2. In addition, angle detectionunit 127 for detecting the angle of receptacle 2 inclined by incliningunit 120 described above consists of infrared transmission unit 128fixed on support 25 and several flag plates 29a to d mounted on bracket25. Each time flag plates 129 a to d fixed to bracket 115 pass throughinfrared transmission unit 128 and shade infrared light, output signalsare transmitted to controller 130.

Since the inclination angle setting device of receptacle 2 is configuredas described above, when the inclination angle of receptacle 2 forcooking is set beforehand and motor 21 is started to incline receptacle2, angle detection unit 127 operates at the preset angle to stop theoperation of motor 21 and start brake 26 in order to maintain theinclination of receptacle 2 at the preset angle. Normally, after thedetection of input signals from limit switch 22 at the start of cooking,the angle detection unit detects the preset angle of the receptacle withthe number of flags passing by infrared transmission unit 128 so thatpot 7 becomes horizontal.

The controller with timer 43 is configured as shown in FIG. 5, andincorporates cooking programs in which cooking procedures are specifiedfor each type of cooking shown in the time charts of FIG. 7. Therefore,when the users of this cooker put ingredients into the pot and selecttheir desired cooking course from courses 47a to n for input into inputinterface 40, ingredients are automatically cooked according to theirdesired cooking course.

The operation of the cooker in case of the "saute cours" in FIG. 7(a)will be described using the time chart. Ingredients are placed into pot7 and receptacle 2 is inclined by starting angle control motor 21 at atime of t₀. At a time t₁ when the inclination angle becomes θd (presetinclination angle), angle detection unit 129d begins to operate to stopangle control motor 21 and start brake 26 to maintain the angle of thepot at θd and heat pot 7 by turning on heating coil 6 while rotating thepot by driving pot rotating motor 18a. At a time of t₂ when preset time(t₂ -t₁) passes, timer 43 begins to operate to stop the rotation andheating of pot 7. At the same time, the timer releases brake 26 andstarts angle control motor 21 to incline receptacle 2 toward theopposite direction. When receptacle 2 returns to the horizontalposition, angle detection unit 127a operates to start brake 26 to stopreceptacle 2 at the original position, thus completing cooking. Thecontroller automatically controls all processes from the inclination ofreceptacle 2 at the start of cooking to the return to the horizontalposition at the end of cooking.

Curry and stew shown in FIG. 7 (b) as well as other meals canautomatically be prepared with the similar operation of the controller.

FIG. 7 (a) and (b) are time charts for the operation of each unit at thestart of cooking when pot 7 is on horizontal in each cooking course. Theoperation of each unit will be described using FIG. 7 (c) when pot 7 isout of horizontal. FIG. 7 (c) is a time chart for the "saute course"shown in FIG. 7 (a) when pot 7 is out of horizontal at the start ofcooking. Ingredients are placed into pot 7 and inclining unit 20 isactuated so that pot 7 becomes horizontal until the detection of inputsignals from limit switch 33. After the detection of input signals fromlimit switch 33, ingredients are sauteed according to a program shown inFIG. 7 (a).

In this embodiment, an infrared sensor is used as angle detection unit127, but a magnetic sensor can be used instead of the infrared sensor.However, when the magnetic sensor is used, it is recommended not to turnon the heating coils during the angle control of the receptacle, takeninto consideration influence on the line of magnetic force by heatingcoils.

Another method for angle detection is to mount an encoder on axis 24.

Furthermore, the gears shown in the embodiment are not the only anglecontrol means, but ball screws, links and cams can serve this purpose.

According to the invention, a rotary cooker incorporates pot rotationdriving means, induction heating means for the pot, and pot inclinationangle setting means with an angle detection unit so that the inclinationangle of the pot can be automatically selected according to a presetcooking program during cooking. Therefore, cooking is automated bypresetting a cooking program according to type of cooking, thus greatlysaving cooking time and labor and greatly improving the operational easeof the rotary cooker.

FIG. 8 (a) is a diagram showing the side of a cooker according to thefourth embodiment, FIG. 8 (b) an enlarged diagram of an angle detectionunit, FIG. 8 (c) a diagram showing a partial cross-section of the frontof the embodiment. FIG. 9 is a diagram of cooking control configuration,and FIGS. 10 (a), (b), (c) and (d) are cooking time charts. In thesefigures, number 2 is a receptacle, 7 pot, 18 rotation driving unit, 18amotor, 18b driving wheels, 120 inclining unit (angle control unit), 21motor, 22 first gear, 23 second gear, 24 axis, 124 bracket, 26 brake,127 angle detection sensor, 128 infrared transmission unit, 128a to dflange plates, 130 controller, 1 base, 20 support, 33 first heatingcoil, 34 second heating coil, 35 first heating coil input control unit,36 second heating coil input control unit, 37 limit switch, 40 inputinterface, 41 output interface, 42 clock control unit, 43 timer, 44 CPU,45 memory, 46 power supply, and 47a and b cooking course input switches.

As shown in these figures, a rotary cooker according to the presentinvention incorporates pot 7, rotation driving unit 8 for rotating pot7, receptacle 2 which consists of first heating coil 33 and secondheating coil 34 for induction heating pot 7 and housing 115 for housingthese heating coils, an inclination angle setting device comprisinginclining unit 120 for inclining receptacle 2, brake 26 and angledetection sensor 127, heating coil input control units 35 and 36 forcontrolling the inputs of heating coils 33 and 34, respectively, andcontroller 130.

Since the inclining unit 120 is fitted with motor 21, first gear 22 andsecond gear 23, when motor 21 is started, bracket 25 fixed on secondgear 23 rotates on axis 24 at the same time as gears 22 and 23 rotate.As a result, receptacle 2 fixed on bracket 24 is inclined. Angledetection sensor 127 consists of infrared transmission unit 128 fixed onsupport 1 and several flag plates 129a to d mounted on bracket 124. Flagplates 129a to d mounted on bracket 124 output signals each time theypass through infrared transmission unit 128 to shade infrared rays. Whenflag plate 129a is aligned with infrared transmission unit 128, pot 7 ison horizontal position. The inclination angle of pot 7 becomes larger inthe order of flag plates 129b, 129c and 129d which are aligned with theinfrared transmission unit. As an example, to incline receptacle 2 atθd, the cooker is set in such a way that flag plate 129d outputs signalswhen it passes by infrared transmission unit 128. When receptacle 2 isinclined at θd, motor 21 of the inclining unit stops operation and brake26 is started to maintain receptacle 2 at θd.

Normally, a specified angle is detected with the number of flags passingby angle detection sensor 127 after the detection of input signals fromlimit switch 37 at the start of cooking so that pot 7 becomeshorizontal.

Heating coils consist of first heating coil 33 for heating the side ofthe pot and second heating coil 34 for heating the bottom of the pot,and first heating coil input control unit 35 and second heating coilinput control unit 36 are used to control the input of each coilindependently.

Controller 130 equipped with timer 43 is configured as shown in FIG. 9,and incorporates cooking programs in which cooking procedures shown inthe time charts of FIG. 10 are specified for each type of cooking. Asdescribed above, the inclination angle and heating method of the pot canbe changed, and accordingly, very complicated cooking procedures can beprogrammed, thus expanding the number of meals to be prepared by thecooker. When users put cooking ingredients into the pot of the cookerand select their desired cooking course from courses 47 a to n for inputinto input interface 40, the cooker automatically prepares the desiredmeals.

The operation of the cooker in case of sauteing course 47a shown in FIG.10 (a) will be described using a time chart. Cooking ingredients are putinto pot 7 and inclining unit 20 is actuated at a time of t_(o) toincline receptacle 2. When the receptacle is inclined at a specifiedangle, angle detection sensor 127 begins to operate to stop anglecontrol motor 21 and start brake 26 at t₁ in order to maintain pot 7 atthe specified angle. At the same time, timer 43 is started and potrotation driving unit 18 is activated to rotate the pot, and first andsecond heating coils 33 and 34 are turned on to heat pot 7 by rotatingit. At t₂ when specified time (t₂ -t₁) passes, timer 43 operates to stopthe rotation and heating of pot 7 and at the same time releases brake 26to start inclining unit 120 in order to return receptacle 2 to theoriginal position. At t₃, when receptacle 2 returns to the horizontalposition, angle detection sensor 127 operates to start brake 26 so thatreceptacle 2 stops at the original position, thus completing cooking.The controller automatically controls all these processes from theinclination of receptacle 2 to the completion of cooking when receptacle2 returns to the horizontal position.

FIG. 9 (b) is a time chart for preparing curry using heating coils 33and 34. The cooking procedure based on this time chart will bedescribed. Put ingredients into pot 7 and start motor 21 of incliningunit 120 at a time of t_(o) to incline receptacle 2. At t₄ when theinclination of receptacle 2 reaches a specified angle, angle detectionsensor 127 operates to output signals to the controller. Then, anglecontrol motor 21 stops operation and brake 26 and timer 43 are started.At the same time, rotation driving motor 18a is started to rotate thepot and first and second heating coils 33 and 34 are turned on to heatpot 7, thus starting sauteing ingredients. At t₅ when a specified timepasses, timer 43 begins to operate and heating coils 33 and 34 and potrotation motor 18a stop operation. At the same time, the angle settingdevice begins to operate to return the inclination of receptacle 2 tothe original angle. At t₆ when receptacle 2 returns to the horizontalposition, angle detection sensor 127 and pot rotation motor 8a begin tooperate and heating coils 23 and 24 are turned on to heat pot 7 which ison horizontal and does not rotate, thus starting boiling. At t₇ when aspecified time passes, timer 43 operates to stop heating pot 7 and theangle setting device is actuated to begin inclining receptacle 2. At t₈,when the inclination of the receptacle reaches a specified angle, angledetection sensor 127 operates to stop motor 21 of the inclining unit inorder to maintain the specified angle. At the same time, the pot isrotated and the second heating coil is turned on to heat the pot fromthe bottom. At t₉ when a specified time passes, timer 43 operates tostop the rotation and heating of pot 7 and inclining unit 120 is alsoactivated to return the inclination of receptacle 2 to the originalangle. When receptacle 2 becomes horizontal, angle detection sensor 127operates to stop the operation of inclining unit 120, thus completingall the operations of the cooker including the timer at t10. In thisway, the cooker has two heating coils whose inputs are controlledindependently, thus making it possible to set complicated cookingprograms and prepare haute cuisine.

With the similar operation of the cooker, it is possible to prepareelaborate meals, but the cooker can also be used to prepare simple mealslike "tempura" shown in FIG. 10 (c).

FIG. 3 (a), (b), and (c) are time charts for the operation of the cookerin case of each cooking course when pot 7 is on horizontal at the startof cooking. The operation of the cooker will be described when pot 7 isout of horizontal position at the start of cooking, using FIG. 3 (d).FIG. 3 (d) is a time chart for sauteing course 47 (a) shown in FIG. 3(a) when pot 7 is out of horizontal position at the start of cooking.Cooking ingredients are placed into pot 7 and inclining unit 120 isactuated until the detection of input signals from limit switch 37 sothat pot 7 becomes horizontal. After the detection of input signals fromlimit switch 37, a sauteing course carried out according to a programshown in FIG. 3 (a).

In this embodiment, an infrared sensor is used as angle detection sensor27, but a magnetic sensor can be used as an alternative. However, when amagnetic sensor is used, it is recommended not to turn on heating coilsduring the angle control of the receptacle, taking into considerationinfluence on the line of magnetic force by heating coils.

Another angle detection method is possible by using an encoder mountedon axis 24.

Furthermore, the gears of the embodiment are not the only incliningunit, but ball screws, links and cams can service this purpose.

According to the invention, a rotary cooker comprises an inclinationsetting device with an angle detection sensor for inclining a pot,heating means for heating the bottom and side of the pot independentlywith each input controllable separately, and a controller with a timer.It incorporates cooking programs to be set according to type of cookingand cooks automatically according to the programs. Therefore, it has thefollowing excellent advantages:

(1) Less labor required for cooking even foods of considerablecomplexity due to automatic cooking.

(2) Failure-free cooking of complicated foods by anyone.

(3) The availability of a wider range of cooking methods.

(4) Greater ease of use of rotary cookers.

FIG. 11 (a) shows the side of an embodiment of a cooker according to thefifth embodiment and FIG. 11 (b) is an enlarged diagram of its key part.In the figures, number 2 is a receptacle, 6 heating coil, 7 pot, 215housing, 220 rotation speed changer, 221 motor, 222 motor axis, 223eccentric pulley a, 224 eccentric pulley b, 225 belt, 226 tensionpulley, 227 driving axis, 228 support frame, and 229 and 230 drivingwheels. This embodiment is also equipped with an angle control unit anda controller described in FIG. 33. As shown in the figures, in therotary cooker according to the invention, rotation speed changer 220which consists of eccentric pulley a 223 fixed on axis 222 of drivingmotor 221, pulley b 224, belt 225 for connecting pulleys a and b andtension pulley 226 lies between driving motor 221 and driving axis 227of driving wheels 229 and 230 for driving the rotation of pot 7.

To cook using this rotary cooker, receptacle 2 with pot 7 and heatingcoil 6 for heating pot 7 is inclined at a specified angle by aninclining unit (not shown in the figures) and pot 7 is heated by heatingcoil 6 while being rotated by a rotation driving unit including saidrotation speed changer 220.

At this time, when driving motor 221 is started, pulley a 223 is rotatedeccentrically as pulley a 223 is fixed on axis 222 eccentrically. As aresult, the rotation speed of pulley b 224 changes within one rotation.Therefore, pot 7 rotates while changing its rotation speed within onerotation and accordingly, the rotation of pot 7 becomes irregular,resulting in the complex movement of cooking ingredients within pot 7.In this way, in case of sauteing, the pot can provide excellent cookingperformance that cannot be achieved by cooking pots with fixed rotationspeed.

Rotation speed changer 220 of this embodiment is not the only means tochange rotation speed. Other systems such as activation rate control andphase control can be used to change the rotation speed of motor 221.

According to the invention, a rotary cooker comprises a pot rotationspeed changer, and accordingly, the rotation of the pot during sauteingfor instance, becomes irregular, resulting in the complex movement ofcooking ingredients within the pot and enhanced cooking performance.

FIG. 12 is a diagram illustrating the configuration embodiment of anelectromagnetic cooker according to the sixth embodiment and FIG. 13 isa diagram showing an X--X cross-section of FIG. 12. The numbers in thisfigure refer to the same or equivalent parts as those of FIG. 33;however, since the embodiment shown in FIG. 12 is partially different instructure, it will be explained in some detail.

In FIG. 12, number 301 is a main unit, 302 receptacle, and 307 pot. Anon-magnetic material with low thermal conductivity such as ceramics isused in the inside of receptacle 302 and a magnetic material in pot 307.Particularly, an iron-based metal material with high magneticpermeability containing manganese is the best suited for the pot. Number306 is an induction heating coil installed inside receptacle 302, and305 heat insulator. A detailed diagram of induction heating coil 306 isomitted, but the coil is made up from a sheathing which covers conductor361 and a thermal insulator such as mica. As shown in FIG. 14, conductor361 is coiled like a rectangular spiral to form circular coil 360 andinstalled inside receptacle 302 for heating the side of inclined pot 307near the lowest part. Number 308 is a rotary motor, and 381 and 382rollers. Roller 381 is fixed on rotary motor 308 and roller 382 makesfriction contact with the outside of pot 307 and roller 381. 341 is asupport fixed on main unit 301, 342 inclining motor, 343 output axis,344 gears, 345 inclining axis, and 346 bracket. These units includinginclining motor 342 constitute an angle control unit described in FIG.33. Bracket 346 is fixed on the bottom Of receptacle 302 and incliningaxis 345 is fitted with a brake not shown in the figure. 314 isingredients within pot 307, 316 controller, 317 switch, and 318 and 319limit switches.

The operation of the electromagnetic cooker according to the inventionin case of fried rice will be described as an example.

Pot 307 is set in receptacle 302 and switch 317 of controller 316 isturned on. Then, inclining motor 342 is actuated to incline pot 307 atan angle of θ via output axis 343, gears 344 and inclining axis 345. Atboth limits of the range of angle θ, limit switches 318 and 319 areactivated to protect receptacle 302 and main unit 301 from collision.When an exciting current with a high frequency of 320 to 350 KHz isapplied to induction heating coil 306, magnetic flux is generated by theexcitation of induction heating coil 306 and an alternating eddy currentflows inside pot 307 through receptacle 302 under the influence ofelectromagnetic induction, thus generating Joule heat. As a result, heatgenerated through electromagnetic induction begins to spread rapidlyfrom the lowest part of inclined pot 307. Rotary motor 308 is driven torotate pot 307 with rollers 381 and 382 and at the same time, a properamount of cooking oil is put into pot 307 and heated by hot pot 307,thus spreading all over the inside of pot 307. After the oil has beenproperly spread, meat and vegetables are put into the pot. Meat andvegetables are collected in the lowest part of pot 307 and mixed withheated oil. After the meat and vegetables have been sauteed, boiled riceis put into the pot. Afterwards, necessary seasonings and otheringredients are added, and heat and rotation are applied again for acertain time. The rice, meat and vegetables are well mixed and friedrice is done. After cooking, induction heating coil 306 and switch 317of controller 316 are turned off to stop the rotation and heating of pot307 which now goes back to the horizontal position. When remaining heatgoes away, fried rice is dished up and ready to serve.

FIG. 15 is a diagram showing key parts of another embodiment of anelectromagnetic cooker according to the present invention. In thisembodiment, conductor 361 is coiled spirally to form coil 360 which iscurved to have two sides 362 and 363 corresponding to the side andbottom of the pot. Induction heating coil 306 made of this coil 360 isvery similar in shape to the outline of ingredients 314 collectingbetween the bottom and the side of inclined pot 307. Therefore,ingredients 314 are heated effectively, thus increasing heatingefficiency.

In the above embodiment, pot 307 is rotated by rotary motor 308 inreceptacle 302 through friction between rollers 381 and 382. However,the pot can be rotated by driving gears fixed on the sealed rotationaxis from the outside. In addition, induction heating coil 306 has onlyone unit of conductor 361 as shown in the figure, but more than one unitof the conductor can be used as well as more than one unit of coil 360.In the embodiment, pot 307 has no lid. The use of transparent material,such as reinforced glass, for a part or all of pot lid provides theconvenience of observing the pot contents as they cook.

The invention relates to an electromagnetic cooker which has aninduction heating coil for heating a pot near the lowest part of theinclined pot.

As a result, a part of the inclined pot where ingredients gather isheated concentratedly to the highest temperature.

Therefore, according to the invention, it is possible to provide aneconomical electromagnetic cooker with a simple configuration which canprepare good meals quickly and has a high heating efficiency.

FIG. 16 is a diagram illustrating the configuration of anelectromagnetic cooker according to the seventh embodiment. The same orcorresponding units of the embodiment shown in FIG. 16 have the samenumbers as FIG. 33, but other units differ from those shown in FIG. 33in structure and will be described in details.

In FIG. 16, number 301 is a main unit, 302 receptacle, and 307 pot. Anon-magnetic material with low thermal conductivity such as ceramics isused in the inside of receptacle 302. A magnetic material is used in pot307. Particularly, an iron-based metal material with high magneticpermeability containing manganese is the best suited for the pot. Number306 is an induction heating coil installed inside receptacle 302, and305 heat insulator. 308 is a rotary motor and.381 and 382 are rollers.Roller 381 is fixed on rotary motor 308 and roller 382 makes frictioncontact with roller 81 and the outer periphery of pot 307. 341 is asupport fixed on main unit 301, 342 inclining motor, 343 output axis,344 gears, 345 inclining axis and 346 bracket. These units includinginclining motor 342 constitute an angle control unit described in FIG.33. Bracket 346 is fixed on the bottom of receptacle 302 at one end andinclining axis 345 with a brake not shown in the figure at the otherend. 314 is cooking ingredients within pot 307, 316 controller, 317switch and 318 and 319 limit switches.

Number 20 is a position detector for detecting the position of pot 307,and 371 is a cut on flange 372 of pot 307 (FIG. 17). Position detector320 consists of light emitting device 322 and light detection device323, for instance, both of which face each other with flange 372 of pot307 between them, as shown in the figure,

The operation of the cooker with this configuration according to thisinvention will be described in case of fried rice.

Pot 307 is set in receptacle 302 and switch 317 of controller 316 isturned on. Then, inclining motor 324 is actuated to incline pot 307 atan angle of θ via output axis 343, gears 344 and inclining axis 345. Atboth limits of the range of angle θ, limit switches 318 and 319 areactivated to protect receptacle 302 and main unit 301 from collision.After an exciting current with a high frequency of 320 to 350 KHz isapplied to induction heating coil 306, magnetic flux is generated by theexcitation of induction heating coil 306 and an alternating eddy currentflows inside pot 307 through receptacle 302 under the influence ofelectromagnetic induction, thus generating Joule heat. As a result, pot307 begins to be heated by heat generated by electromagnetic inductionrapidly. Rotary motor 308 is driven to rotate pot 307 with rollers 381and 382 and at the same time, a proper amount of cooking oil is put intopot 307 and heated by hot pot 307, thus spreading all over the inside ofpot 307. When the oil has been properly spread, meat and vegetables areadded. Meat and vegetables are mixed and sauteed by rotation.

Meanwhile, when cut 371 comes to position detector 320 by the rotationof pot 307, light emitted from light emitting device 322 18 received bylight detecting device 323. As a result, the rotation of pot 307 isstopped by controller 316 via rotary motor 308 and the lowest part ofpot 307 is heated concentratedly to high temperatures to heat meat andvegetables which require strong heat. After concentrated heating, therotation speed returns to the original, and mixing and heating byrotation start again. The operation of the cooker for this type ofcooking is shown in the timing charts of FIG. 18 (a), (b) and (c). InFIG. 18 (d), detection cycle T is twice as long as that of FIG. 18 (a)(once every two rotations). After meat and vegetables have been wellsauteed by intermittent concentrated heating, boiled rice is put intothe pot. Afterwards, necessary seasonings and other ingredients areadded, and concentrated heating by stopping rotation intermittently andmixing/heating by rotation are applied alternately. Then, rice, meat andvegetables are well mixed and fried rice is done. After cooking,induction heating coil 306 and switch 317 of controller 316 are turnedoff to stop the rotation and heating of pot 307 which now goes back tothe horizontal position. When remaining heat goes away, fried rice isdished up and ready to serve.

FIG. 19 is a diagram illustrating the configuration of anotherembodiment of an electromagnetic cooker according to the invention. Theembodiment differs from the embodiment shown in FIG. 33 in the structureof induction heating coil 306. A detailed diagram of induction heatingcoil 306 is omitted, but the coil is made up from a sheathing whichcovers conductor 361 and a thermal insulator such as mica. Conductor361, for instance, is coiled like a rectangular spiral to form circularcoil 360 as shown in FIG. 20 (a). In FIG. 20 (b), conductor 361 is usedto form bilateral curved coil 360. Induction heating coil 306 made up ofcoil 360 shown in FIG. 22 (b) is very similar in shape to the outline ofingredients 314 collected between the bottom and the side of inclinedpot 307. Either coil shown in FIG. 20 (a) and (b) is installed insidereceptacle 302 to heat concentratedly the lowest part of inclined pot307 and spreads gradually radiat heat all over pot 307. In thisembodiment, a part of the pot where ingredients 314 gather is heatedconcentratedly, resulting in a high thermal efficiency and a small sizeand low production cost for induction heating coil 306.

In the above embodiment, position detector 320 is used to stop therotation of pot 307 at a specified position for concentrated heating. Atimer can also be used to stop or decelerate the rotation of pot 307, orusers can operate manually for concentrated heating while looking atcooking proceeding. In this embodiment, pot 307 has no lid, but the useof transparent material such as reinforced glass for a part or all ofthe pot lid provides the convenience of observing the pot contents asthey cook.

This embodiment relates to an electromagnetic cooker which changescontact time between ingredients and a heated cooking pot regularly orat random through the control of the rotation of the pot. As a result,mixing/heating by rotation and concentrated heating by stopping ordecelerating the rotation are combined to saute food efficiently.Particularly, when induction heating coils for induction heating the potare installed at the side of the lowest part and the corner of theinclined pot, a part of the inclined and rotated pot where ingredientsgather is heated concentratedly to the highest temperature, thus furtherincreasing a thermal efficiency.

Therefore, the cooker can cook vegetables with fresh colors as well asgood meat.

Therefore, according to the invention, it is possible to provide aneconomical electromagnetic cooker with a simple configuration which canprepare good meals quickly and has a high thermal efficiency.

FIG. 21 is a cooker according to the eighth embodiment. The numbers inthis figure refer to the same or equivalent parts as those of FIG. 33;however, since FIG. 21 is partially different in structure, it will beexplained in some detail.

In FIG. 21, 301 is the main unit and baseplate, 302 receptacle, and 307cooking pot. A non-magnetic material with low thermal conductivity, suchas ceramic, is used for the inner surface of receptacle 302, whilemagnetic material is used for the inner surface of cooking pot 307, withiron-based metal with high magnetic permeability being especiallysuitable. Number 306 is an induction heating coil built into the cookingpot 302, 305 heat insulator, 308 rotary motor, and 381 and 382 rollers.Roller 381 is built into rotary motor 308, and roller 382 makes frictioncontact with the outside of cooking pot 307 and roller 381. Number 341is a support that is fixed to main unit 301, 342 inclining motor, 343output axis, 344 gears, 345 inclining axis, and 346 bracket. Bracket 346is fixed to the bottom of receptacle 302 and to inclining axis 345 whichis provided with a brake that is not shown. Number 314 is ingredientswithin cooking pot 307, 316 control unit, 317 switch, and 318 and 319limit switches.

Number 320 is a pot lid, 321 packing, and 322 clasp. Number 323 is aport built-into the center of pot lid 320, 324 port cover, and 325hinge. Rotating cover 324 with hinge 325 acting as a fulcrum opens andcloses port 323. As shown in the figure, when cover 324 is placed overport 323, the free moving part of cover 324 lies flush with the outerrim of port 323 to provide tight closure.

The cooking procedures for a cooking pot according to the invention andin this configuration will now be explained. Pot lid 320 is placed ontocooking pot 307 and closed with clasp 322, and the cooking pot is placedinto receptacle 302. After cooking pot 307 is in place, switch 317 ofthe control unit is turned on to activate inclining motor 342, andcooking pot 307 is inclined to an angle of θ through output axis 343,gears 344, and inclining axis 345. These parts including inclining motor342 constitute the angle control unit explained in FIG. 33. Limit switch318 or 319 is activated at each limit of the range of angle θ toprotects receptacle 302 and other parts from collision. shown in FIG. 3(a) when pot 7 is out of horizontal position at the

When a current with a high frequency of about 20-50 KHz is applied toinduction heating coil 306, alternating eddy currents are generatedthrough electromagetic induction via receptacle 302, to produce jouleheat inside cooking pot 307 which lies within the magnetic field. As aresult, the heat produced through electromagnetic induction beginsheating up cooking pot 307 at a high rate. When cooking pot 307 hasheated up, pot lid 324 is rotated on hinge 325, which acts as a fulcrum,to provide access to the cooking pot, and a proper amount of cooking oilis added through port 323. Rotary motor 308 is activated and cooking pot307 is rotated via rollers 381 and 382, and the oil is spread withincooking pot 307. After the oil has been properly spread, port 323 isopened again and meat or vegetables are added. Afterwards, previouslyprepared rice and seasonings are added through port 323 in the same way,and heat and rotation are applied again for a certain length of time.The rice and ingredients are well mixed and cooked. After cooking hasbeen completed, induction heating coil 306 and switch 317 of controlunit 316 are turned off. The rotation and heating of cooking pot 307 arestopped, and cooking pot 307 returns to horizontal position. Aftersufficient cooling has occurred, the prepared fried rice can be served.After the meal, cooking pot 307 and pot lid 320 are washed separately.

In the above embodiment, cooking pot 307 is inclined by inclining axis345 on top of support 341 and rotated by roller 382 by friction.However, means for inclination and rotation are not limited to those ofthis embodiment. Furthermore, although not included in the aboveexplanation, the use of transparent material, such as reinforced glass,for a part or all of pot lid 320 provides the convenience of observingthe pot contents as they cook. Also, cooking pot 307 was placed inreceptacle 302; however, other suitable means of mounting the cookingpot may also be used.

This invention relates to an electromagnetic cooker with a pot lid thatis provided with a port. When the pot and pot lid are set into themounting apparatus, they are rotated as the entire assembly is inclined.For this reason, it maintains an airtight seal of the contents andeliminates the wear that usually takes place at the point of contactbetween the cooking pot and the lid through friction. Since ingredientsand seasonings are added through the port into the cooking pot, spillingout of contents is minimized. Moreover, not only can the cooking pot betaken out for cleaning, it can also be used as an ordinary cooking potwith a lid.

The above characteristics make it possible to provide an electromagneticcooker that is high in sanitation and applicability, as well as easy touse.

FIG. 22 shows a cross-section, FIG. 23 a partial cross-section of thekey parts, and FIG. 24 a diagram showing the configuration of thecontroller of a cooker according to the ninth embodiment.

In FIG. 22, 401 is the base, 402 the main unit of the rotary cooker, 406induction heating coil, and 407 cooking pot. Cooking pot 407 can bedetached from main unit 402. Number 408 is a pot driving unit, 417 anglecontrol unit for changing the inclination angle of main unit 402 andcooking pot 407. Numbers 418 and 419 are manual switches built into base401 for selecting the type of food and the inclination angle of the potand other conditions. These consist of, for example, a number ofswitches arranged in a horizontal row. Switch 418 is for selecting suchcooking courses as "curry" and "saute," while manual switch 419 is usedto select such cooking conditions as the inclination angle of cookingpot 407, the rotation speed, and the heat output. Number 420 is acontact that touches the bottom of cooking pot 407 and 421 heat sensorbuilt inside contact 420. A non-magnetic metal with high thermalconductivity, such as aluminum, would be suitable for contact 420.

An enlarged view of the surrounding configuration of contact 420 isshown in FIG. 23. (The following refers to FIG. 23.) Number 424 is a potbase which receives cooking pot 407, 425 and 426 springs, 427 stopperthat is attached to base 424. Contact 420 is pressed upward by spring426, and is held down at the top by stopper 427. Number 428 is a potdetection switch which detects the presence of the pot, 429 pin whichpresses down pot detection switch 428 via spring 425, 430 guide thatslides up and down pin 429, and 431 a guide base for guide 430. Number432 is a coil base for fixing induction heating coil 406, 422 athermometer (FIG. 22) for measuring the temperature of cooking pot 407through heat sensor 421, and 423 control unit for controlling potdriving unit 408, inclination angle control unit 417 and the heat outputof induction heat coil 406 through the the output of thermometer 422.

Number 440 in FIG. 24 is an input interface, 441 output interface, 442clock control unit, 443 timer, 444 CPU, 445 memory, 446 power switch,447 heat output control, and 448 buzzer.

In the case of a rotary cooker of the structure described above, powerswitch 446 is turned on and cooking pot 407 is placed into main unit402. After ingredients are placed into cooking pot 407, cooking is begunat the desired inclination angle, rotation speed, heat output ofinduction heat coil 406, and other cooking conditions that are setthrough manual switch 419.

When cooking pot 407 is placed into main unit 402, contact 420 ispressed downward by the weight of cooking pot 407 in the directionindicated by arrow A, and maintains the cooking pot at a horizontalposition higher than pot base 424. At this time, the spring pressure ofsprings 425 and 426 places contact 420 into contact with the bottom ofcooking pot 407, causing contact 420 and cooking pot 407 to be thermallyjoined. At the same time, pin 429 follows the downward movement ofcontact 420, and guided by guide 430, presses against pot detectionswitch 428, by which the presence of cooking pot 407 on top of main unit402 is detected. In reverse, when cooking pot 407 is removed, pin 429springs upward to release pot detection switch 428, and the "absence" ofcooking pot 407 is detected.

Controller 423, which is provided with CPU 444 and whose configurationis shown in FIG. 24, incorporates programs of cooking conditions forvarious cooking procedures in the form of time charts such as that usedin the example in FIG. 25 for a "saute course."As a result, afterputting ingredients into cooking pot 407 and inputting the desiredcooking course into input interface 440 through manual switch 418, thedesired cooking is done automatically.

The action of the rotary cooker in the case of the "saute course" inFIG. 25 will be explained next on the basis of the time chart and thechanges in the temperature of contact 420. After cooking pot 407 isplaced into main unit 402 and cooking is started with the cooking timeset at t0, angle control unit 417 changes the angle of main unit 402 andinduction heat coil 406 is activated through heat output control 447.When the inclination angle of main unit 402 reaches a certain angle, theoperation of angle control unit 417 stops and pot driving unit 408begins and cooking pot 407 starts rotating. After cooking has started,heat sensor 421 within contact 420 monitors the temperature of cookingpot 407 as it is heated by induction heat coil 406. When a time of tO-t1has elapsed and the temperature becomes T1 proper to add oil in the pot,buzzer 448 sounds to instruct the user to add oil. After the oil isadded, control unit 423 adjusts the current to induction heating coil406 so that temperature Tmax is not exceeded if a certain amount of timepasses while the ingredients have not been added. After ingredients areadded to cooking pot 407 at time t2, the temperature measurment of heatsensor 421, which had dropped, begins to rise again. When thetemperature rises to Te (at a time t3), the cooking of the ingredientsis completed and current to induction heating coil 406 is cut. After thecurrent is cut, cooking pot 407 maintains a relatively high temperature.To prevent the cooked ingredients from burning, pot driving unit 408continues the rotating action, mixing the ingredients for a little whileeven after current to induction heat coil 406 is shut off. After acertain duration or when cooking pot 407 cools down to a certaintemperature, pot driving unit 408 stops. Angle control unit 417 restoresthe horizontal position and the "saute course" is ended. All cookingoperations, from inclination angle of main unit 402 at the start ofcooking to the return to the horizontal position at the end of cookingare controlled automatically by controller 423.

In addition, after ingredients are added, pot driving unit 408 may becontrolled in such a way that allows the rotation of cooking pot 407 tobe modified through controller 423.

As shown in FIG. 25, controller 423 controls the temperature in such away that Tmax is not exceeded by adjusting the input to inductionheating coil 406 during the period from t1 to t2, thus preventing theoccurrence of abnormally high temperatures in pot 407. Furthermore, amaximum time of from t1 to t2 may be set, and the activation time ofinduction heating coil 406 may be automatically cut off when the maximumtime is reached. This type of configuration would prevent burning of theingredients or damage to cooking pot 407 by overheating, scorchingcaused by activation of induction heating coil 406 for long periods, orthe occurrence of fire.

It is also possible through controller 423 to automatically control thetemperature of cooking pot 407 so that it does not exceed Tmax even whenheat output has been adjusted manually by manual switch 419.

In the above embodiment, contact 420 is fixed to main unit 402. However,it is also possible to use metal balls or metal rollers, etc. which arehigh in thermal conductivity and resistant to wear In contact 420. Inaddition, contact 420 which contains heat sensor 421 can be attached tomain unit 402 in such a way that allows it to be rotated and put inflexible contact at approximately the center of the bottom of cookingpot 407 to allow temperature measurements at the point of contact. In acooker with contact 420 in the configuration described in the twoembodiments above, the point of contact between contact 420 and cookingpot 407 would be free of wear and higher in thermal linkage. Moreover,though the embodiment described cooking pot 407 without a lid, the useof a lid made of transparent material such as reinforced glass for apart or all of pot lid would allow the user to view the contents of thepot during cooking for greater convenience.

As described in the above explanation, the following features of theinvention constitute a rotary cooker that has: (1) means of detectingthe temperature of the cooking pot through the use of a heat sensor thatis thermally linked with the cooking pot; (2) means of controlling thecooking conditions such as pot driving means, pot heating means, andangle control means based on the output from the means of temperaturedetection; and (3) programs based on cooking conditions for specificfoods that have been stored in memory to allow the automatic preparationof those foods through operation of the programs. From this, thefollowing results may be expected:

(1) Less labor required for cooking even foods of considerablecomplexity due to automatic cooking.

(2) Failure-free cooking of complicated foods by anyone.

(3) The availability of a wider range of cooking methods.

(4) Greater ease of use of rotary cookers.

The placement of a contact at the center of the cooking pot's rotationgreatly minimizes the effects of friction, etc. Such effects would bereduced even more by enabling the contact to the main unit to be rotatedby using, for example, metal balls. This would have the added benefit ofenhanced thermal linkage for higher accuracy in temperaturemeasurements.

For these reasons, this invention would make possible the provision of arotary cooker with features such as those listed above in (1) to (4).

An embodiment of a cooker according to the tenth embodiment is explainedbelow referring to figures. FIG. 26 is a cross-section of a cookeraccording to the tenth embodiment. Numbers in the figure which are thesame as those in FIG. 33 refer to the same or equivalent parts. Number417 is an angle control unit which changes the angle of receptacle 402in the angles indicated by arrows A to D via action of such parts asmotor and gear that are not represented in the figure, 418 switch forselecting such cooking courses as "saute" or "curry," 419 manualswitches operated by the user to select such cooking conditions as potinclination angle, pot rotation speed, and heat output, 520 contact, 521heat sensor contained within contact 520, 460 moving means for bringingcontact 520 into or out of contact with the outside of cooking pot 407,422 temperature measuring circuit for measuring the temperature pickedup by heat sensor 521, 423 means of control, 524 pot base for mountingcooking pot 407, and 408c and 408d rollers for transferring therotational driving force of pot driving means 408 to cooking pot 407.

FIG. 27 is a cross-section of driving means 460 of FIG. 26. In thefigure, 525 is a driving motor that moves contact 520 up and down, 526gear attached to the axis of driving motor 525, 527 shaft that holds therack fixed to contact 520 which meshes with gear 526, 536 and 537 ringsattached to shaft 527, 534 flag fixed to shaft 527, 535 sensor thatdetects the position of flag 534, 528 motor base that fixes drivingmotor 525, 529 guide that slides up and down shaft 527, 530 guide basefor receiving guide 529, 531 adjustment spring that corrects thepositional relationship between shaft 527 and contact 520, 532 pressurespring that presses contact 520 against the bottom of cooking pot 407,and 533 a base that fixes moving means 460 to receptacle 402.

FIG. 28 is a block drawing of control means 423 of FIG. 26. In thefigure, 540 is an input interface, 541 output interface, 542 clockcontrol unit, 543 timer, 544 CPU, 545 memory for storing cookingprograms executed by CPU 544 shown in FIG. 30 and information for thecooking courses of FIG. 31, 518a switch for sauteing, 518b switch forcurry, 546 contact driving circuit, 547 pot driving circuit, 548 anglecontrol circuit, 549 coil driving circuit, and 550 buzzer.

The operation of the cooker is explained next. FIG. 29 (a) is a timingchart that indicates the driving control of contact 520 in theembodiment of a cooker according to the invention. Here, angle controlunit 417 changes the angle of receptacle 402 at time (to) and the angleadjustment ends at time (ta). Electricity is then applied to drivingmotor 525, which rotates gear 526 in the direction to cause contact 520to rise upward and contact the bottom of cooking pot 407. Sensor 535detects this condition, turns off the electricity to driving motor 525and the temperature of heat sensor 521 is measured through temperaturemeasuring circuit 422 for a duration of (tc) after an elapse of time(tb) during which the temperatures of heat sensor 521 and cooking pot407 become the same. Time (tb) is determined on the basis of the shapeof contact 520, the area of contact between it and cooking pot 407, andthe heat capacity and other factors. The specification of (tc) as themeasurement time aims at raising the reliability of the measurementdata. After the temperature of cooking pot 407 has. been measured inthis way, electricity is applied to driving motor 525 and gear 526rotates reversely so that contact 520 is pulled downward through ring537, separating contact 520 from the bottom of cooking pot 407. Whensensor 535 detects this condition, it cuts the electricity to drivingmotor 525. The time (td) required for this series of actions from thelifting of contact 520 to the re-lifting of contact 520 is taken as onetemperature measurement cycle. By repeating the cycle a number of times,the temperature of cooking pot 407 is measured intermittently. In thisway, it is possible to decrease the amount of wear of contact 520 evenwhen measuring the temperature of cooking pot 407 while it is rotating.

FIG. 29 (b) is a timing chart indicating the relationship between thecontrol of contact 520 and the control of pot driving means 408. Itshows that the rotation of cooking pot 407 is stopped during the timecontact 520 is touching cooking pot 407, thereby sharply decreasing theamount of wear of contact 520.

FIG. 29 (c) is a timing chart indicating the relationship between thecontrol of contact 520 and the control of induction heating coil 406. Itshows that the heating of cooking pot 407 is stopped during the timecontact 520 is touching cooking pot 407, thereby preventing the heatingof contact 520 itself by electromagnetic induction, thus preventingdamage to the temperature measuring circuit by electromagneticinduction.

FIG. 29 (d) is a timing chart indicating the relationship between thecontrol of contact 520 and the control of both pot driving means 408 andinduction heating coil 406. It shows that the rotation and inductionheating of cooking pot 407 is stopped during the time contact 520 istouching cooking pot 407.

From FIGS. 29 (a) to (d), it is seen that temperature measurement may bestarted from time (to), which corresponds to the start of angle controlunit 417.

FIG. 30 is a flowchart of the cooking programs for an embodiment of acooker according the invention. FIG. 31 is a diagram explaining thecontrol information for the cooking courses of the embodiment. In stepS1, electricity is applied to induction heating coil 406. At the sametime, in step S2, angle control unit 417 adjusts the inclination angleof receptacle 402. In step S3, cooking pot 407 is rotated. Step S4 is awaiting period for the temperature of cooking pot 407 to reachappropriate temperature T1. When the temperature reaches T1, buzzer 550sounds in step S5 to inform the user that cooking pot 407 has reachedthe appropriate temperature. In step S6, a check of whether thetemperature of cooking pot 407 has risen above the allowable maximumtemperature Tmax. If it has, induction heating coil 406 is shut off instep S7. In this way, the user need not worry about overheating whenaway from the cooker. If in step S6 the temperature is found to be belowTmax, power is applied again to induction heating coil 406 in step S8.In step S9, the temperature is checked whether it is below T1. If not,oil or ingredients 514 are not added and the sequence returns to stepS6. If the temperature is found to be below T1 in step S9, oil andingredients 514 are added, and the sequence goes to step S10 in whichcooking takes place according to the control information of the cookingcourse shown in FIG. 31.

In FIG. 31, cooking course information consists of pot temperature Taccording to time t, and control information for pot driving means 408and angle control unit 417. For example, the curve of pot temperature Tdefines the standard change in the pot temperature after the addition ofingredients 514, etc. at time T2. As shown in the curve for pottemperature T, the temperature drops sharply when the specified amountof ingredients is added, then rises gradually as the ingredients areheated, finally reaching the proper temperature for the specified typeof food. This temperature is maintained for a length of time specifiedfor the food, after which cooking of the food is defined to be completedat time (t3). CPU 544 reads the cooking course control information frommemory 545 at specified times and controls induction heating coil 406 sothat the actual measurement temperature at each point conforms to thecurve for pot temperature T. In the same way, it also controls potdriving means 408 and angle control unit 417 according to the controlinformation of the cooking course. Thus, it becomes possible to changeboth the rotation speed of cooking pot 407 and the angle of cooking pot407 according to the control information of the cooking course.

In case the amount of ingredients added to cooking pot 407 exceeds thespecified amount, the curve of pot temperature T drops even more sharplyand the rise in the temperature of the ingredients will lag behind asshown by curve Tr indicated as a dotted line in the figure. Thus it maybe thought that cooking will not be completed by time (t3). However,even in such a case, CPU 544 can raise the level of power applied toinduction heating coil 406 so that the change in actual pot temperaturethereafter matches the curve of pot temperature T in the figure. Thuscooking can still be completed time (t3). Or, CPU 544 is able toascertain the extent by which amount of ingredients exceeds thespecified amount based on the actual drop in pot temperature, andrespond by increasing the time interval for reading the information ofpot temperature T from memory 545 based on the difference. As a result,cooking takes place according to temperature course Tr, and cooking canstill be completed at time (t4). In this way, irregular amounts ofingredients can be properly cooked using only a single set of controlinformation for a standard cooking course.

Returning to FIG. 30, when the completion of cooking is determined instep S11, power to induction heating coil 406 is cut step S12, rotationof cooking pot 407 is stopped in step S13, and receptacle 402 isreturned to horizontal position in step S14.

FIG. 32 is a timing chart for the operation of an embodiment of a rotarycooker according to the invention for a saute course. In the figure,when cooking pot 407 is placed in receptacle 402 and cooking begins attime (to), angle control unit 417 changes the angle of receptacle 402,and at the same time, power is applied to induction heating coil 406.Afterwards, angle control unit 417 stops when the inclination ofreceptacle 402 reaches a specified angle, pot driving means 408 isactivated and rotation of cooking pot 407 begins. From the start ofcooking at (to), the temperature of cooking pot 407 is measured momentby moment. When the temperature T1 for adding oil is reached, buzzer 550sounds to inform the user to add oil. After oil is added at time (t1), acertain length of time passes until the addition of ingredients 514,during which power to induction heating coil 406 is regulated so thatthe temperature of cooking pot 407 does not exceed the allowable maximumtemperature Tmax. When ingredients 514 are added at time (t2), thetemperature of pot 407 drops sharply, then after a while, begins to riseagain. At time (t3) when temperature Te is reached, cooking is completedand power to induction heating coil 406 is cut. At this time, thetemperature of cooking pot 407 is high, so pot driving means 408continues to operate, mixing the ingredients to prevent them fromburning. After a certain period of time or when it is ascertained thatthe cooking pot has dropped to a certain temperature, power to potdriving means 408 is cut and angle control unit 417 returns receptacle402 to its original angle and cooking is completed. In this way, controlis automatically conducted from the point when receptacle 402 begins toincline to the completion of cooking and the return of receptacle 402 toits original horizontal position.

In the above embodiment, contact 520 is designed to touch the centerportion of the bottom of cooking pot 407; however, it may also bedesigned to touch another part of the bottom of cooking pot 407 or thesurface of the outer side.

In the above embodiment, the means for moving contact 520 was indicatedas a combination of rack and gear; however, this combination may besubstituted with other means (such as a cam and link unit).

Moreover, since contact 520 is thermally linked with cooking pot 407,contact 520 would best be made of material with a high thermalconductivity (such as aluminum).

As explained above, this invention makes it possible to heat a rotatingcooking pot from the outside by induction heating and to make propermeasurements of the temperature of a cooking pot by causing a contactincorporating a heat sensing element to come into or out of contact withthe outside surface of the cooking pot. Moreover, since it controls theheating means based on both information that defines the change incooking temperature and the actual measurement temperatures, it enablesthe user to produce uniform cooking results regardless of his or hercooking sense or experience, and therefore further simplifies the use ofrotary cookers.

What is claimed is:
 1. A cooker comprising:a receptacle for holding apot which holds ingredients; means for heating the pot in thereceptacle; means for supporting the receptacle so that the pot isinclinable; a motor for providing a driving force to the means forsupporting to incline the receptacle; and a controller for controllingthe motor.
 2. The cooker of claim 1 wherein the means for supportingcomprises:a bracket rigidly coupled to the receptacle; a first gearrigidly coupled to the bracket for rotating the bracket about an axiswhen the first gear rotates; and means for coupling the motor to thefirst gear.
 3. The cooker of claim 1 further comprising a limit switchpositioned to be contacted by the receptacle at a predetermined angle,and means for changing operation of the motor in response to activationof the limit switch.
 4. The cooker of claim 1 further comprising:means,coupled to the controller, for maintaining the receptacle at a desiredangle.
 5. The cooker of claim 1 wherein the pot has a bottom portion andside portions, the cooker further comprising a heater whichcomprises:heating coils includinga first coil for heating the bottomportion of the pot, and a second coil for heating the side portion ofthe pot; and means for controlling and switching the coils so that thefirst and second coils are operable separately or simultaneously.
 6. Thecooker of claim 1 further comprising an angle detector for detecting theangle of the receptacle, and memory for storing an angle settingprogram, wherein the controller controls the angle of incline of thereceptacle in response to the detected angle and the angle settingprogram.
 7. The cooker of claim 6 further comprising a timer and memoryfor storing an activation time setting program, wherein the controllercontrols the heater so that the heater heats the receptacle for a timeindicated by the activation time setting program.
 8. The cooker of claim1 further comprising means for rotating the pot relative to thereceptacle when the pot is in the receptacle.
 9. A cooker having areceptacle for receiving a pot for holding ingredients, wherein thereceptacle is supported by a main unit so that the pot is freelyinclinable, the cooker comprising:an angle control unit having a motorwhich provides a force; and means for coupling the motor to thereceptacle so that the motor causes the receptacle to incline.
 10. Thecooker of claim 9 further comprising a controller for controlling theangle control unit.
 11. The cooker of claim 9 wherein the pot has abottom portion and side portions, the cooker further comprising a heaterwhich comprises:heating coils includinga first coil for heating thebottom portion of the pot, and a second coil for heating the sideportion of the pot; and means for controlling and switching the coils sothat the first and second coils can be selectively controlled to areoperable separately or simultaneously.
 12. The cooker of claim 9 furthercomprising an angle detector for detecting the angle of the receptacle,and memory for storing an angle setting program, wherein the controllercontrols the angle of incline of the receptacle in response to thedetected angle and the angle setting program.
 13. A cooker having areceptacle for receiving a pot for holding ingredients and a heater forheating said pot by induction, wherein the receptacle is supported by amain unit so that the pot is inclinable, the cooker comprising:an anglecontrol unit which provides a driving force for inclining saidreceptacle; and a controller for controlling said angle control unitwherein the pot has a bottom portion and side portions, wherein theheater comprises: heating coils includinga first coil for heating thebottom portion of the pot, and a second coil for heating the sideportions of the pot; and means for controlling and switching the coilsso that the first and second coils are operable separately orsimultaneously.
 14. The cooker of claim 13 further comprising a timerand memory for storing an activation time setting program, wherein thecontroller controls the heater so that the heater heats the receptaclefor a time indicated by the activation time setting program.
 15. Thecooker of claim 13 further comprising means for rotating the potrelative to the receptacle when the pot is in the receptacle.